<?php
/**
 * Smarty Internal Plugin Smarty Template  Base
 *
 * This file contains the basic shared methodes for template handling
 *
 * @package    Smarty
 * @subpackage Template
 * @author     Uwe Tews
 */

/**
 * Class with shared template methodes
 *
 * @package    Smarty
 * @subpackage Template
 */
abstract class Smarty_Internal_TemplateBase extends Smarty_Internal_Data {

	/**
	 * fetches a rendered Smarty template
	 *
	 * @param string $template         the resource handle of the template file or template object
	 * @param mixed  $cache_id         cache id to be used with this template
	 * @param mixed  $compile_id       compile id to be used with this template
	 * @param object $parent           next higher level of Smarty variables
	 * @param bool   $display          true: display, false: fetch
	 * @param bool   $merge_tpl_vars   if true parent template variables merged in to local scope
	 * @param bool   $no_output_filter if true do not run output filter
	 *
	 * @return string rendered template output
	 */
	public function fetch($template = null, $cache_id = null, $compile_id = null, $parent = null, $display = false, $merge_tpl_vars = true, $no_output_filter = false) {
		if ($template === null && $this instanceof $this->template_class)
		{
			$template = $this;
		}
		if (!empty($cache_id) && is_object($cache_id))
		{
			$parent = $cache_id;
			$cache_id = null;
		}
		if ($parent === null && ($this instanceof Smarty || is_string($template)))
		{
			$parent = $this;
		}
		// create template object if necessary
		$_template = ($template instanceof $this->template_class) ? $template : $this->smarty->createTemplate($template, $cache_id, $compile_id, $parent, false);
		// if called by Smarty object make sure we use current caching status
		if ($this instanceof Smarty)
		{
			$_template->caching = $this->caching;
		}
		// merge all variable scopes into template
		if ($merge_tpl_vars)
		{
			// save local variables
			$save_tpl_vars = $_template->tpl_vars;
			$save_config_vars = $_template->config_vars;
			$ptr_array = array($_template);
			$ptr = $_template;
			while (isset($ptr->parent))
			{
				$ptr_array[] = $ptr = $ptr->parent;
			}
			$ptr_array = array_reverse($ptr_array);
			$parent_ptr = reset($ptr_array);
			$tpl_vars = $parent_ptr->tpl_vars;
			$config_vars = $parent_ptr->config_vars;
			while ($parent_ptr = next($ptr_array))
			{
				if (!empty($parent_ptr->tpl_vars))
				{
					$tpl_vars = array_merge($tpl_vars, $parent_ptr->tpl_vars);
				}
				if (!empty($parent_ptr->config_vars))
				{
					$config_vars = array_merge($config_vars, $parent_ptr->config_vars);
				}
			}
			if (!empty(Smarty::$global_tpl_vars))
			{
				$tpl_vars = array_merge(Smarty::$global_tpl_vars, $tpl_vars);
			}
			$_template->tpl_vars = $tpl_vars;
			$_template->config_vars = $config_vars;
		}
		// dummy local smarty variable
		if (!isset($_template->tpl_vars['smarty']))
		{
			$_template->tpl_vars['smarty'] = new Smarty_Variable;
		}
		if (isset($this->smarty->error_reporting))
		{
			$_smarty_old_error_level = error_reporting($this->smarty->error_reporting);
		}
		// check URL debugging control
		if (!$this->smarty->debugging && $this->smarty->debugging_ctrl == 'URL')
		{
			if (isset($_SERVER['QUERY_STRING']))
			{
				$_query_string = $_SERVER['QUERY_STRING'];
			}
			else
			{
				$_query_string = '';
			}
			if (false !== strpos($_query_string, $this->smarty->smarty_debug_id))
			{
				if (false !== strpos($_query_string, $this->smarty->smarty_debug_id . '=on'))
				{
					// enable debugging for this browser session
					setcookie('SMARTY_DEBUG', true);
					$this->smarty->debugging = true;
				}
				elseif (false !== strpos($_query_string, $this->smarty->smarty_debug_id . '=off'))
				{
					// disable debugging for this browser session
					setcookie('SMARTY_DEBUG', false);
					$this->smarty->debugging = false;
				}
				else
				{
					// enable debugging for this page
					$this->smarty->debugging = true;
				}
			}
			else
			{
				if (isset($_COOKIE['SMARTY_DEBUG']))
				{
					$this->smarty->debugging = true;
				}
			}
		}
		// must reset merge template date
		$_template->smarty->merged_templates_func = array();
		// get rendered template
		// disable caching for evaluated code
		if ($_template->source->recompiled)
		{
			$_template->caching = false;
		}
		// checks if template exists
		if (!$_template->source->exists)
		{
			if ($_template->parent instanceof Smarty_Internal_Template)
			{
				$parent_resource = " in '{$_template->parent->template_resource}'";
			}
			else
			{
				$parent_resource = '';
			}
			throw new SmartyException("Unable to load template {$_template->source->type} '{$_template->source->name}'{$parent_resource}");
		}
		// read from cache or render
		if (!($_template->caching == Smarty::CACHING_LIFETIME_CURRENT || $_template->caching == Smarty::CACHING_LIFETIME_SAVED) || !$_template->cached->valid)
		{
			// render template (not loaded and not in cache)
			if (!$_template->source->uncompiled)
			{
				$_smarty_tpl = $_template;
				if ($_template->source->recompiled)
				{
					if ($this->smarty->debugging)
					{
						Smarty_Internal_Debug::start_compile($_template);
					}
					$code = $_template->compiler->compileTemplate($_template);
					if ($this->smarty->debugging)
					{
						Smarty_Internal_Debug::end_compile($_template);
					}
					if ($this->smarty->debugging)
					{
						Smarty_Internal_Debug::start_render($_template);
					}
					try
					{
						ob_start();
						eval("?>" . $code);
						unset($code);
					} catch (Exception $e)
					{
						ob_get_clean();
						throw $e;
					}
				}
				else
				{
					if (!$_template->compiled->exists || ($_template->smarty->force_compile && !$_template->compiled->isCompiled))
					{
						$_template->compileTemplateSource();
					}
					if ($this->smarty->debugging)
					{
						Smarty_Internal_Debug::start_render($_template);
					}
					if (!$_template->compiled->loaded)
					{
						include($_template->compiled->filepath);
						if ($_template->mustCompile)
						{
							// recompile and load again
							$_template->compileTemplateSource();
							include($_template->compiled->filepath);
						}
						$_template->compiled->loaded = true;
					}
					else
					{
						$_template->decodeProperties($_template->compiled->_properties, false);
					}
					try
					{
						ob_start();
						if (empty($_template->properties['unifunc']) || !is_callable($_template->properties['unifunc']))
						{
							throw new SmartyException("Invalid compiled template for '{$_template->template_resource}'");
						}
						array_unshift($_template->_capture_stack, array());
						//
						// render compiled template
						//
						$_template->properties['unifunc']($_template);
						// any unclosed {capture} tags ?
						if (isset($_template->_capture_stack[0][0]))
						{
							$_template->capture_error();
						}
						array_shift($_template->_capture_stack);
					} catch (Exception $e)
					{
						ob_get_clean();
						throw $e;
					}
				}
			}
			else
			{
				if ($_template->source->uncompiled)
				{
					if ($this->smarty->debugging)
					{
						Smarty_Internal_Debug::start_render($_template);
					}
					try
					{
						ob_start();
						$_template->source->renderUncompiled($_template);
					} catch (Exception $e)
					{
						ob_get_clean();
						throw $e;
					}
				}
				else
				{
					throw new SmartyException("Resource '$_template->source->type' must have 'renderUncompiled' method");
				}
			}
			$_output = ob_get_clean();
			if (!$_template->source->recompiled && empty($_template->properties['file_dependency'][$_template->source->uid]))
			{
				$_template->properties['file_dependency'][$_template->source->uid] = array($_template->source->filepath, $_template->source->timestamp, $_template->source->type);
			}
			if ($_template->parent instanceof Smarty_Internal_Template)
			{
				$_template->parent->properties['file_dependency'] = array_merge($_template->parent->properties['file_dependency'], $_template->properties['file_dependency']);
				foreach ($_template->required_plugins as $code => $tmp1)
				{
					foreach ($tmp1 as $name => $tmp)
					{
						foreach ($tmp as $type => $data)
						{
							$_template->parent->required_plugins[$code][$name][$type] = $data;
						}
					}
				}
			}
			if ($this->smarty->debugging)
			{
				Smarty_Internal_Debug::end_render($_template);
			}
			// write to cache when nessecary
			if (!$_template->source->recompiled && ($_template->caching == Smarty::CACHING_LIFETIME_SAVED || $_template->caching == Smarty::CACHING_LIFETIME_CURRENT))
			{
				if ($this->smarty->debugging)
				{
					Smarty_Internal_Debug::start_cache($_template);
				}
				$_template->properties['has_nocache_code'] = false;
				// get text between non-cached items
				$cache_split = preg_split("!/\*%%SmartyNocache:{$_template->properties['nocache_hash']}%%\*\/(.+?)/\*/%%SmartyNocache:{$_template->properties['nocache_hash']}%%\*/!s", $_output);
				// get non-cached items
				preg_match_all("!/\*%%SmartyNocache:{$_template->properties['nocache_hash']}%%\*\/(.+?)/\*/%%SmartyNocache:{$_template->properties['nocache_hash']}%%\*/!s", $_output, $cache_parts);
				$output = '';
				// loop over items, stitch back together
				foreach ($cache_split as $curr_idx => $curr_split)
				{
					// escape PHP tags in template content
					$output .= preg_replace('/(<%|%>|<\?php|<\?|\?>)/', '<?php echo \'$1\'; ?>', $curr_split);
					if (isset($cache_parts[0][$curr_idx]))
					{
						$_template->properties['has_nocache_code'] = true;
						// remove nocache tags from cache output
						$output .= preg_replace("!/\*/?%%SmartyNocache:{$_template->properties['nocache_hash']}%%\*/!", '', $cache_parts[0][$curr_idx]);
					}
				}
				if (!$no_output_filter && !$_template->has_nocache_code && (isset($this->smarty->autoload_filters['output']) || isset($this->smarty->registered_filters['output'])))
				{
					$output = Smarty_Internal_Filter_Handler::runFilter('output', $output, $_template);
				}
				// rendering (must be done before writing cache file because of {function} nocache handling)
				$_smarty_tpl = $_template;
				try
				{
					ob_start();
					eval("?>" . $output);
					$_output = ob_get_clean();
				} catch (Exception $e)
				{
					ob_get_clean();
					throw $e;
				}
				// write cache file content
				$_template->writeCachedContent($output);
				if ($this->smarty->debugging)
				{
					Smarty_Internal_Debug::end_cache($_template);
				}
			}
			else
			{
				// var_dump('renderTemplate', $_template->has_nocache_code, $_template->template_resource, $_template->properties['nocache_hash'], $_template->parent->properties['nocache_hash'], $_output);
				if (!empty($_template->properties['nocache_hash']) && !empty($_template->parent->properties['nocache_hash']))
				{
					// replace nocache_hash
					$_output = str_replace("{$_template->properties['nocache_hash']}", $_template->parent->properties['nocache_hash'], $_output);
					$_template->parent->has_nocache_code = $_template->parent->has_nocache_code || $_template->has_nocache_code;
				}
			}
		}
		else
		{
			if ($this->smarty->debugging)
			{
				Smarty_Internal_Debug::start_cache($_template);
			}
			try
			{
				ob_start();
				array_unshift($_template->_capture_stack, array());
				//
				// render cached template
				//
				$_template->properties['unifunc']($_template);
				// any unclosed {capture} tags ?
				if (isset($_template->_capture_stack[0][0]))
				{
					$_template->capture_error();
				}
				array_shift($_template->_capture_stack);
				$_output = ob_get_clean();
			} catch (Exception $e)
			{
				ob_get_clean();
				throw $e;
			}
			if ($this->smarty->debugging)
			{
				Smarty_Internal_Debug::end_cache($_template);
			}
		}
		if ((!$this->caching || $_template->has_nocache_code || $_template->source->recompiled) && !$no_output_filter && (isset($this->smarty->autoload_filters['output']) || isset($this->smarty->registered_filters['output'])))
		{
			$_output = Smarty_Internal_Filter_Handler::runFilter('output', $_output, $_template);
		}
		if (isset($this->error_reporting))
		{
			error_reporting($_smarty_old_error_level);
		}
		// display or fetch
		if ($display)
		{
			if ($this->caching && $this->cache_modified_check)
			{
				$_isCached = $_template->isCached() && !$_template->has_nocache_code;
				$_last_modified_date = @substr($_SERVER['HTTP_IF_MODIFIED_SINCE'], 0, strpos($_SERVER['HTTP_IF_MODIFIED_SINCE'], 'GMT') + 3);
				if ($_isCached && $_template->cached->timestamp <= strtotime($_last_modified_date))
				{
					switch (PHP_SAPI)
					{
						case 'cgi': // php-cgi < 5.3
						case 'cgi-fcgi': // php-cgi >= 5.3
						case 'fpm-fcgi': // php-fpm >= 5.3.3
							header('Status: 304 Not Modified');
							break;

						case 'cli':
							if ( /* ^phpunit */
							!empty($_SERVER['SMARTY_PHPUNIT_DISABLE_HEADERS']) /* phpunit$ */
							)
							{
								$_SERVER['SMARTY_PHPUNIT_HEADERS'][] = '304 Not Modified';
							}
							break;

						default:
							header($_SERVER['SERVER_PROTOCOL'] . ' 304 Not Modified');
							break;
					}
				}
				else
				{
					switch (PHP_SAPI)
					{
						case 'cli':
							if ( /* ^phpunit */
							!empty($_SERVER['SMARTY_PHPUNIT_DISABLE_HEADERS']) /* phpunit$ */
							)
							{
								$_SERVER['SMARTY_PHPUNIT_HEADERS'][] = 'Last-Modified: ' . gmdate('D, d M Y H:i:s', $_template->cached->timestamp) . ' GMT';
							}
							break;

						default:
							header('Last-Modified: ' . gmdate('D, d M Y H:i:s', $_template->cached->timestamp) . ' GMT');
							break;
					}
					echo $_output;
				}
			}
			else
			{
				echo $_output;
			}
			// debug output
			if ($this->smarty->debugging)
			{
				Smarty_Internal_Debug::display_debug($this);
			}
			if ($merge_tpl_vars)
			{
				// restore local variables
				$_template->tpl_vars = $save_tpl_vars;
				$_template->config_vars = $save_config_vars;
			}

			return;
		}
		else
		{
			if ($merge_tpl_vars)
			{
				// restore local variables
				$_template->tpl_vars = $save_tpl_vars;
				$_template->config_vars = $save_config_vars;
			}

			// return fetched content
			return $_output;
		}
	}

	/**
	 * displays a Smarty template
	 *
	 * @param string $template   the resource handle of the template file or template object
	 * @param mixed  $cache_id   cache id to be used with this template
	 * @param mixed  $compile_id compile id to be used with this template
	 * @param object $parent     next higher level of Smarty variables
	 */
	public function display($template = null, $cache_id = null, $compile_id = null, $parent = null) {
		// display template
		$this->fetch($template, $cache_id, $compile_id, $parent, true);
	}

	/**
	 * test if cache is valid
	 *
	 * @param string|object $template   the resource handle of the template file or template object
	 * @param mixed         $cache_id   cache id to be used with this template
	 * @param mixed         $compile_id compile id to be used with this template
	 * @param object        $parent     next higher level of Smarty variables
	 *
	 * @return boolean cache status
	 */
	public function isCached($template = null, $cache_id = null, $compile_id = null, $parent = null) {
		if ($template === null && $this instanceof $this->template_class)
		{
			return $this->cached->valid;
		}
		if (!($template instanceof $this->template_class))
		{
			if ($parent === null)
			{
				$parent = $this;
			}
			$template = $this->smarty->createTemplate($template, $cache_id, $compile_id, $parent, false);
		}

		// return cache status of template
		return $template->cached->valid;
	}

	/**
	 * creates a data object
	 *
	 * @param object $parent next higher level of Smarty variables
	 *
	 * @returns Smarty_Data data object
	 */
	public function createData($parent = null) {
		return new Smarty_Data($parent, $this);
	}

	/**
	 * Registers plugin to be used in templates
	 *
	 * @param string   $type       plugin type
	 * @param string   $tag        name of template tag
	 * @param callback $callback   PHP callback to register
	 * @param boolean  $cacheable  if true (default) this fuction is cachable
	 * @param array    $cache_attr caching attributes if any
	 *
	 * @return Smarty_Internal_Templatebase current Smarty_Internal_Templatebase (or Smarty or Smarty_Internal_Template) instance for chaining
	 * @throws SmartyException when the plugin tag is invalid
	 */
	public function registerPlugin($type, $tag, $callback, $cacheable = true, $cache_attr = null) {
		if (isset($this->smarty->registered_plugins[$type][$tag]))
		{
			throw new SmartyException("Plugin tag \"{$tag}\" already registered");
		}
		elseif (!is_callable($callback))
		{
			throw new SmartyException("Plugin \"{$tag}\" not callable");
		}
		else
		{
			$this->smarty->registered_plugins[$type][$tag] = array($callback, (bool)$cacheable, (array)$cache_attr);
		}

		return $this;
	}

	/**
	 * Unregister Plugin
	 *
	 * @param string $type of plugin
	 * @param string $tag  name of plugin
	 *
	 * @return Smarty_Internal_Templatebase current Smarty_Internal_Templatebase (or Smarty or Smarty_Internal_Template) instance for chaining
	 */
	public function unregisterPlugin($type, $tag) {
		if (isset($this->smarty->registered_plugins[$type][$tag]))
		{
			unset($this->smarty->registered_plugins[$type][$tag]);
		}

		return $this;
	}

	/**
	 * Registers a resource to fetch a template
	 *
	 * @param string                $type     name of resource type
	 * @param Smarty_Resource|array $callback or instance of Smarty_Resource, or array of callbacks to handle resource (deprecated)
	 *
	 * @return Smarty_Internal_Templatebase current Smarty_Internal_Templatebase (or Smarty or Smarty_Internal_Template) instance for chaining
	 */
	public function registerResource($type, $callback) {
		$this->smarty->registered_resources[$type] = $callback instanceof Smarty_Resource ? $callback : array($callback, false);

		return $this;
	}

	/**
	 * Unregisters a resource
	 *
	 * @param string $type name of resource type
	 *
	 * @return Smarty_Internal_Templatebase current Smarty_Internal_Templatebase (or Smarty or Smarty_Internal_Template) instance for chaining
	 */
	public function unregisterResource($type) {
		if (isset($this->smarty->registered_resources[$type]))
		{
			unset($this->smarty->registered_resources[$type]);
		}

		return $this;
	}

	/**
	 * Registers a cache resource to cache a template's output
	 *
	 * @param string               $type     name of cache resource type
	 * @param Smarty_CacheResource $callback instance of Smarty_CacheResource to handle output caching
	 *
	 * @return Smarty_Internal_Templatebase current Smarty_Internal_Templatebase (or Smarty or Smarty_Internal_Template) instance for chaining
	 */
	public function registerCacheResource($type, Smarty_CacheResource $callback) {
		$this->smarty->registered_cache_resources[$type] = $callback;

		return $this;
	}

	/**
	 * Unregisters a cache resource
	 *
	 * @param string $type name of cache resource type
	 *
	 * @return Smarty_Internal_Templatebase current Smarty_Internal_Templatebase (or Smarty or Smarty_Internal_Template) instance for chaining
	 */
	public function unregisterCacheResource($type) {
		if (isset($this->smarty->registered_cache_resources[$type]))
		{
			unset($this->smarty->registered_cache_resources[$type]);
		}

		return $this;
	}

	/**
	 * Registers object to be used in templates
	 *
	 * @param string  $object        name of template object
	 * @param object  $object_impl   the referenced PHP object to register
	 * @param array   $allowed       list of allowed methods (empty = all)
	 * @param boolean $smarty_args   smarty argument format, else traditional
	 * @param array   $block_methods list of block-methods
	 * @param array   $block_functs  list of methods that are block format
	 *
	 * @return Smarty_Internal_Templatebase current Smarty_Internal_Templatebase (or Smarty or Smarty_Internal_Template) instance for chaining
	 * @throws SmartyException if any of the methods in $allowed or $block_methods are invalid
	 */
	public function registerObject($object_name, $object_impl, $allowed = array(), $smarty_args = true, $block_methods = array()) {
		// test if allowed methodes callable
		if (!empty($allowed))
		{
			foreach ((array)$allowed as $method)
			{
				if (!is_callable(array($object_impl, $method)))
				{
					throw new SmartyException("Undefined method '$method' in registered object");
				}
			}
		}
		// test if block methodes callable
		if (!empty($block_methods))
		{
			foreach ((array)$block_methods as $method)
			{
				if (!is_callable(array($object_impl, $method)))
				{
					throw new SmartyException("Undefined method '$method' in registered object");
				}
			}
		}
		// register the object
		$this->smarty->registered_objects[$object_name] = array($object_impl, (array)$allowed, (boolean)$smarty_args, (array)$block_methods);

		return $this;
	}

	/**
	 * return a reference to a registered object
	 *
	 * @param string $name object name
	 *
	 * @return object
	 * @throws SmartyException if no such object is found
	 */
	public function getRegisteredObject($name) {
		if (!isset($this->smarty->registered_objects[$name]))
		{
			throw new SmartyException("'$name' is not a registered object");
		}
		if (!is_object($this->smarty->registered_objects[$name][0]))
		{
			throw new SmartyException("registered '$name' is not an object");
		}

		return $this->smarty->registered_objects[$name][0];
	}

	/**
	 * unregister an object
	 *
	 * @param string $name object name
	 *
	 * @return Smarty_Internal_Templatebase current Smarty_Internal_Templatebase (or Smarty or Smarty_Internal_Template) instance for chaining
	 */
	public function unregisterObject($name) {
		if (isset($this->smarty->registered_objects[$name]))
		{
			unset($this->smarty->registered_objects[$name]);
		}

		return $this;
	}

	/**
	 * Registers static classes to be used in templates
	 *
	 * @param string $class      name of template class
	 * @param string $class_impl the referenced PHP class to register
	 *
	 * @return Smarty_Internal_Templatebase current Smarty_Internal_Templatebase (or Smarty or Smarty_Internal_Template) instance for chaining
	 * @throws SmartyException if $class_impl does not refer to an existing class
	 */
	public function registerClass($class_name, $class_impl) {
		// test if exists
		if (!class_exists($class_impl))
		{
			throw new SmartyException("Undefined class '$class_impl' in register template class");
		}
		// register the class
		$this->smarty->registered_classes[$class_name] = $class_impl;

		return $this;
	}

	/**
	 * Registers a default plugin handler
	 *
	 * @param callable $callback class/method name
	 *
	 * @return Smarty_Internal_Templatebase current Smarty_Internal_Templatebase (or Smarty or Smarty_Internal_Template) instance for chaining
	 * @throws SmartyException if $callback is not callable
	 */
	public function registerDefaultPluginHandler($callback) {
		if (is_callable($callback))
		{
			$this->smarty->default_plugin_handler_func = $callback;
		}
		else
		{
			throw new SmartyException("Default plugin handler '$callback' not callable");
		}

		return $this;
	}

	/**
	 * Registers a default template handler
	 *
	 * @param callable $callback class/method name
	 *
	 * @return Smarty_Internal_Templatebase current Smarty_Internal_Templatebase (or Smarty or Smarty_Internal_Template) instance for chaining
	 * @throws SmartyException if $callback is not callable
	 */
	public function registerDefaultTemplateHandler($callback) {
		if (is_callable($callback))
		{
			$this->smarty->default_template_handler_func = $callback;
		}
		else
		{
			throw new SmartyException("Default template handler '$callback' not callable");
		}

		return $this;
	}

	/**
	 * Registers a default template handler
	 *
	 * @param callable $callback class/method name
	 *
	 * @return Smarty_Internal_Templatebase current Smarty_Internal_Templatebase (or Smarty or Smarty_Internal_Template) instance for chaining
	 * @throws SmartyException if $callback is not callable
	 */
	public function registerDefaultConfigHandler($callback) {
		if (is_callable($callback))
		{
			$this->smarty->default_config_handler_func = $callback;
		}
		else
		{
			throw new SmartyException("Default config handler '$callback' not callable");
		}

		return $this;
	}

	/**
	 * Registers a filter function
	 *
	 * @param string   $type filter type
	 * @param callback $callback
	 *
	 * @return Smarty_Internal_Templatebase current Smarty_Internal_Templatebase (or Smarty or Smarty_Internal_Template) instance for chaining
	 */
	public function registerFilter($type, $callback) {
		$this->smarty->registered_filters[$type][$this->_get_filter_name($callback)] = $callback;

		return $this;
	}

	/**
	 * Unregisters a filter function
	 *
	 * @param string   $type filter type
	 * @param callback $callback
	 *
	 * @return Smarty_Internal_Templatebase current Smarty_Internal_Templatebase (or Smarty or Smarty_Internal_Template) instance for chaining
	 */
	public function unregisterFilter($type, $callback) {
		$name = $this->_get_filter_name($callback);
		if (isset($this->smarty->registered_filters[$type][$name]))
		{
			unset($this->smarty->registered_filters[$type][$name]);
		}

		return $this;
	}

	/**
	 * Return internal filter name
	 *
	 * @param callback $function_name
	 *
	 * @return string internal filter name
	 */
	public function _get_filter_name($function_name) {
		if (is_array($function_name))
		{
			$_class_name = (is_object($function_name[0]) ? get_class($function_name[0]) : $function_name[0]);

			return $_class_name . '_' . $function_name[1];
		}
		else
		{
			return $function_name;
		}
	}

	/**
	 * load a filter of specified type and name
	 *
	 * @param string $type filter type
	 * @param string $name filter name
	 *
	 * @throws SmartyException if filter could not be loaded
	 */
	public function loadFilter($type, $name) {
		$_plugin = "smarty_{$type}filter_{$name}";
		$_filter_name = $_plugin;
		if ($this->smarty->loadPlugin($_plugin))
		{
			if (class_exists($_plugin, false))
			{
				$_plugin = array($_plugin, 'execute');
			}
			if (is_callable($_plugin))
			{
				$this->smarty->registered_filters[$type][$_filter_name] = $_plugin;

				return true;
			}
		}
		throw new SmartyException("{$type}filter \"{$name}\" not callable");
	}

	/**
	 * unload a filter of specified type and name
	 *
	 * @param string $type filter type
	 * @param string $name filter name
	 *
	 * @return Smarty_Internal_Templatebase current Smarty_Internal_Templatebase (or Smarty or Smarty_Internal_Template) instance for chaining
	 */
	public function unloadFilter($type, $name) {
		$_filter_name = "smarty_{$type}filter_{$name}";
		if (isset($this->smarty->registered_filters[$type][$_filter_name]))
		{
			unset ($this->smarty->registered_filters[$type][$_filter_name]);
		}

		return $this;
	}

	/**
	 * preg_replace callback to convert camelcase getter/setter to underscore property names
	 *
	 * @param string $match match string
	 *
	 * @return string replacemant
	 */
	private function replaceCamelcase($match) {
		return "_" . strtolower($match[1]);
	}

	/**
	 * Handle unknown class methods
	 *
	 * @param string $name unknown method-name
	 * @param array  $args argument array
	 */
	public function __call($name, $args) {
		static $_prefixes = array('set' => true, 'get' => true);
		static $_resolved_property_name = array();
		static $_resolved_property_source = array();

		// method of Smarty object?
		if (method_exists($this->smarty, $name))
		{
			return call_user_func_array(array($this->smarty, $name), $args);
		}
		// see if this is a set/get for a property
		$first3 = strtolower(substr($name, 0, 3));
		if (isset($_prefixes[$first3]) && isset($name[3]) && $name[3] !== '_')
		{
			if (isset($_resolved_property_name[$name]))
			{
				$property_name = $_resolved_property_name[$name];
			}
			else
			{
				// try to keep case correct for future PHP 6.0 case-sensitive class methods
				// lcfirst() not available < PHP 5.3.0, so improvise
				$property_name = strtolower(substr($name, 3, 1)) . substr($name, 4);
				// convert camel case to underscored name
				$property_name = preg_replace_callback('/([A-Z])/', array($this, 'replaceCamelcase'), $property_name);
				$_resolved_property_name[$name] = $property_name;
			}
			if (isset($_resolved_property_source[$property_name]))
			{
				$_is_this = $_resolved_property_source[$property_name];
			}
			else
			{
				$_is_this = null;
				if (property_exists($this, $property_name))
				{
					$_is_this = true;
				}
				else if (property_exists($this->smarty, $property_name))
				{
					$_is_this = false;
				}
				$_resolved_property_source[$property_name] = $_is_this;
			}
			if ($_is_this)
			{
				if ($first3 == 'get')
					return $this->$property_name;
				else
					return $this->$property_name = $args[0];
			}
			else if ($_is_this === false)
			{
				if ($first3 == 'get')
					return $this->smarty->$property_name;
				else
					return $this->smarty->$property_name = $args[0];
			}
			else
			{
				throw new SmartyException("property '$property_name' does not exist.");

				return false;
			}
		}
		if ($name == 'Smarty')
		{
			throw new SmartyException("PHP5 requires you to call __construct() instead of Smarty()");
		}
		// must be unknown
		throw new SmartyException("Call of unknown method '$name'.");
	}

}

?>
